Ziwei Jiao ¹ Liping Zhang ² Ake Zhang ² Ruoqi Li ² Kui Zhang ² Zhen Wu ² Zitong Kang ² Yuquan Wei ^2* Longli Zhang ² Yue Wang ² Xiong Shi ² Ji Li ²

• ¹ Yili Normal University, Yili, China
• ² China Agricultural University, Beijing, China

The aim of this study was to investigate the impact of incorporating mature compost on the harmlessness and maturity level of composting from swine manure and carcasses from industrialized pig farms in continuously running large-scale silo 2 reactor systems. The potential human or animal bacterial pathogens and core bacterial community in composting were analyzed by high throughput sequencing of 16S rRNA gene amplicons. Results showed that the addition of mature compost in GD group significantly increased the temperature of all depths, accumulated temperature of compost, and germination index (75.43%) compared to that in HN group without mature compost. High throughput sequencing revealed that the dominated genus in GD were Ureibacillus, Lactobacillus, Corynebacterium, Staphylococcus and Jeotgalicoccus, and the addition of mature compost could significantly increase the relative abundance of Ureibacillus (16.82%) that was associated with the biodegradation of organics. A total of 421 potential bacterial pathogens were detected and the dominated genera of pathogens were Streptococcus, Staphylococcus, Anaerococcus. The potential pathogen in GD group with mature compost was reduced from 7.16% to 0.77%, significantly lower than that (2.97%) in HN group. Together, these findings revealed mature compost addition in large-scale reactor composting could accelerate the harmless and humification process, which provide an effective and environmentally-friendly scheme to deal with the main organic wastes in intensive pig farms.